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1/*
2 * Real Time Clock interface for Linux on Atmel AT91RM9200
3 *
4 * Copyright (C) 2002 Rick Bronson
5 *
6 * Converted to RTC class model by Andrew Victor
7 *
8 * Ported to Linux 2.6 by Steven Scholz
9 * Based on s3c2410-rtc.c Simtec Electronics
10 *
11 * Based on sa1100-rtc.c by Nils Faerber
12 * Based on rtc.c by Paul Gortmaker
13 *
14 * This program is free software; you can redistribute it and/or
15 * modify it under the terms of the GNU General Public License
16 * as published by the Free Software Foundation; either version
17 * 2 of the License, or (at your option) any later version.
18 *
19 */
20
21#include <linux/module.h>
22#include <linux/kernel.h>
23#include <linux/platform_device.h>
24#include <linux/time.h>
25#include <linux/rtc.h>
26#include <linux/bcd.h>
27#include <linux/interrupt.h>
28#include <linux/ioctl.h>
29#include <linux/completion.h>
30
31#include <asm/uaccess.h>
32
33#include <mach/at91_rtc.h>
34
35
36#define AT91_RTC_EPOCH 1900UL /* just like arch/arm/common/rtctime.c */
37
38static DECLARE_COMPLETION(at91_rtc_updated);
39static unsigned int at91_alarm_year = AT91_RTC_EPOCH;
40
41/*
42 * Decode time/date into rtc_time structure
43 */
44static void at91_rtc_decodetime(unsigned int timereg, unsigned int calreg,
45 struct rtc_time *tm)
46{
47 unsigned int time, date;
48
49 /* must read twice in case it changes */
50 do {
51 time = at91_sys_read(timereg);
52 date = at91_sys_read(calreg);
53 } while ((time != at91_sys_read(timereg)) ||
54 (date != at91_sys_read(calreg)));
55
56 tm->tm_sec = bcd2bin((time & AT91_RTC_SEC) >> 0);
57 tm->tm_min = bcd2bin((time & AT91_RTC_MIN) >> 8);
58 tm->tm_hour = bcd2bin((time & AT91_RTC_HOUR) >> 16);
59
60 /*
61 * The Calendar Alarm register does not have a field for
62 * the year - so these will return an invalid value. When an
63 * alarm is set, at91_alarm_year will store the current year.
64 */
65 tm->tm_year = bcd2bin(date & AT91_RTC_CENT) * 100; /* century */
66 tm->tm_year += bcd2bin((date & AT91_RTC_YEAR) >> 8); /* year */
67
68 tm->tm_wday = bcd2bin((date & AT91_RTC_DAY) >> 21) - 1; /* day of the week [0-6], Sunday=0 */
69 tm->tm_mon = bcd2bin((date & AT91_RTC_MONTH) >> 16) - 1;
70 tm->tm_mday = bcd2bin((date & AT91_RTC_DATE) >> 24);
71}
72
73/*
74 * Read current time and date in RTC
75 */
76static int at91_rtc_readtime(struct device *dev, struct rtc_time *tm)
77{
78 at91_rtc_decodetime(AT91_RTC_TIMR, AT91_RTC_CALR, tm);
79 tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year);
80 tm->tm_year = tm->tm_year - 1900;
81
82 pr_debug("%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__,
83 1900 + tm->tm_year, tm->tm_mon, tm->tm_mday,
84 tm->tm_hour, tm->tm_min, tm->tm_sec);
85
86 return 0;
87}
88
89/*
90 * Set current time and date in RTC
91 */
92static int at91_rtc_settime(struct device *dev, struct rtc_time *tm)
93{
94 unsigned long cr;
95
96 pr_debug("%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__,
97 1900 + tm->tm_year, tm->tm_mon, tm->tm_mday,
98 tm->tm_hour, tm->tm_min, tm->tm_sec);
99
100 /* Stop Time/Calendar from counting */
101 cr = at91_sys_read(AT91_RTC_CR);
102 at91_sys_write(AT91_RTC_CR, cr | AT91_RTC_UPDCAL | AT91_RTC_UPDTIM);
103
104 at91_sys_write(AT91_RTC_IER, AT91_RTC_ACKUPD);
105 wait_for_completion(&at91_rtc_updated); /* wait for ACKUPD interrupt */
106 at91_sys_write(AT91_RTC_IDR, AT91_RTC_ACKUPD);
107
108 at91_sys_write(AT91_RTC_TIMR,
109 bin2bcd(tm->tm_sec) << 0
110 | bin2bcd(tm->tm_min) << 8
111 | bin2bcd(tm->tm_hour) << 16);
112
113 at91_sys_write(AT91_RTC_CALR,
114 bin2bcd((tm->tm_year + 1900) / 100) /* century */
115 | bin2bcd(tm->tm_year % 100) << 8 /* year */
116 | bin2bcd(tm->tm_mon + 1) << 16 /* tm_mon starts at zero */
117 | bin2bcd(tm->tm_wday + 1) << 21 /* day of the week [0-6], Sunday=0 */
118 | bin2bcd(tm->tm_mday) << 24);
119
120 /* Restart Time/Calendar */
121 cr = at91_sys_read(AT91_RTC_CR);
122 at91_sys_write(AT91_RTC_CR, cr & ~(AT91_RTC_UPDCAL | AT91_RTC_UPDTIM));
123
124 return 0;
125}
126
127/*
128 * Read alarm time and date in RTC
129 */
130static int at91_rtc_readalarm(struct device *dev, struct rtc_wkalrm *alrm)
131{
132 struct rtc_time *tm = &alrm->time;
133
134 at91_rtc_decodetime(AT91_RTC_TIMALR, AT91_RTC_CALALR, tm);
135 tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year);
136 tm->tm_year = at91_alarm_year - 1900;
137
138 alrm->enabled = (at91_sys_read(AT91_RTC_IMR) & AT91_RTC_ALARM)
139 ? 1 : 0;
140
141 pr_debug("%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__,
142 1900 + tm->tm_year, tm->tm_mon, tm->tm_mday,
143 tm->tm_hour, tm->tm_min, tm->tm_sec);
144
145 return 0;
146}
147
148/*
149 * Set alarm time and date in RTC
150 */
151static int at91_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm)
152{
153 struct rtc_time tm;
154
155 at91_rtc_decodetime(AT91_RTC_TIMR, AT91_RTC_CALR, &tm);
156
157 at91_alarm_year = tm.tm_year;
158
159 tm.tm_hour = alrm->time.tm_hour;
160 tm.tm_min = alrm->time.tm_min;
161 tm.tm_sec = alrm->time.tm_sec;
162
163 at91_sys_write(AT91_RTC_IDR, AT91_RTC_ALARM);
164 at91_sys_write(AT91_RTC_TIMALR,
165 bin2bcd(tm.tm_sec) << 0
166 | bin2bcd(tm.tm_min) << 8
167 | bin2bcd(tm.tm_hour) << 16
168 | AT91_RTC_HOUREN | AT91_RTC_MINEN | AT91_RTC_SECEN);
169 at91_sys_write(AT91_RTC_CALALR,
170 bin2bcd(tm.tm_mon + 1) << 16 /* tm_mon starts at zero */
171 | bin2bcd(tm.tm_mday) << 24
172 | AT91_RTC_DATEEN | AT91_RTC_MTHEN);
173
174 if (alrm->enabled) {
175 at91_sys_write(AT91_RTC_SCCR, AT91_RTC_ALARM);
176 at91_sys_write(AT91_RTC_IER, AT91_RTC_ALARM);
177 }
178
179 pr_debug("%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__,
180 at91_alarm_year, tm.tm_mon, tm.tm_mday, tm.tm_hour,
181 tm.tm_min, tm.tm_sec);
182
183 return 0;
184}
185
186static int at91_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
187{
188 pr_debug("%s(): cmd=%08x\n", __func__, enabled);
189
190 if (enabled) {
191 at91_sys_write(AT91_RTC_SCCR, AT91_RTC_ALARM);
192 at91_sys_write(AT91_RTC_IER, AT91_RTC_ALARM);
193 } else
194 at91_sys_write(AT91_RTC_IDR, AT91_RTC_ALARM);
195
196 return 0;
197}
198/*
199 * Provide additional RTC information in /proc/driver/rtc
200 */
201static int at91_rtc_proc(struct device *dev, struct seq_file *seq)
202{
203 unsigned long imr = at91_sys_read(AT91_RTC_IMR);
204
205 seq_printf(seq, "update_IRQ\t: %s\n",
206 (imr & AT91_RTC_ACKUPD) ? "yes" : "no");
207 seq_printf(seq, "periodic_IRQ\t: %s\n",
208 (imr & AT91_RTC_SECEV) ? "yes" : "no");
209
210 return 0;
211}
212
213/*
214 * IRQ handler for the RTC
215 */
216static irqreturn_t at91_rtc_interrupt(int irq, void *dev_id)
217{
218 struct platform_device *pdev = dev_id;
219 struct rtc_device *rtc = platform_get_drvdata(pdev);
220 unsigned int rtsr;
221 unsigned long events = 0;
222
223 rtsr = at91_sys_read(AT91_RTC_SR) & at91_sys_read(AT91_RTC_IMR);
224 if (rtsr) { /* this interrupt is shared! Is it ours? */
225 if (rtsr & AT91_RTC_ALARM)
226 events |= (RTC_AF | RTC_IRQF);
227 if (rtsr & AT91_RTC_SECEV)
228 events |= (RTC_UF | RTC_IRQF);
229 if (rtsr & AT91_RTC_ACKUPD)
230 complete(&at91_rtc_updated);
231
232 at91_sys_write(AT91_RTC_SCCR, rtsr); /* clear status reg */
233
234 rtc_update_irq(rtc, 1, events);
235
236 pr_debug("%s(): num=%ld, events=0x%02lx\n", __func__,
237 events >> 8, events & 0x000000FF);
238
239 return IRQ_HANDLED;
240 }
241 return IRQ_NONE; /* not handled */
242}
243
244static const struct rtc_class_ops at91_rtc_ops = {
245 .read_time = at91_rtc_readtime,
246 .set_time = at91_rtc_settime,
247 .read_alarm = at91_rtc_readalarm,
248 .set_alarm = at91_rtc_setalarm,
249 .proc = at91_rtc_proc,
250 .alarm_irq_enable = at91_rtc_alarm_irq_enable,
251};
252
253/*
254 * Initialize and install RTC driver
255 */
256static int __init at91_rtc_probe(struct platform_device *pdev)
257{
258 struct rtc_device *rtc;
259 int ret;
260
261 at91_sys_write(AT91_RTC_CR, 0);
262 at91_sys_write(AT91_RTC_MR, 0); /* 24 hour mode */
263
264 /* Disable all interrupts */
265 at91_sys_write(AT91_RTC_IDR, AT91_RTC_ACKUPD | AT91_RTC_ALARM |
266 AT91_RTC_SECEV | AT91_RTC_TIMEV |
267 AT91_RTC_CALEV);
268
269 ret = request_irq(AT91_ID_SYS, at91_rtc_interrupt,
270 IRQF_SHARED,
271 "at91_rtc", pdev);
272 if (ret) {
273 printk(KERN_ERR "at91_rtc: IRQ %d already in use.\n",
274 AT91_ID_SYS);
275 return ret;
276 }
277
278 /* cpu init code should really have flagged this device as
279 * being wake-capable; if it didn't, do that here.
280 */
281 if (!device_can_wakeup(&pdev->dev))
282 device_init_wakeup(&pdev->dev, 1);
283
284 rtc = rtc_device_register(pdev->name, &pdev->dev,
285 &at91_rtc_ops, THIS_MODULE);
286 if (IS_ERR(rtc)) {
287 free_irq(AT91_ID_SYS, pdev);
288 return PTR_ERR(rtc);
289 }
290 platform_set_drvdata(pdev, rtc);
291
292 printk(KERN_INFO "AT91 Real Time Clock driver.\n");
293 return 0;
294}
295
296/*
297 * Disable and remove the RTC driver
298 */
299static int __exit at91_rtc_remove(struct platform_device *pdev)
300{
301 struct rtc_device *rtc = platform_get_drvdata(pdev);
302
303 /* Disable all interrupts */
304 at91_sys_write(AT91_RTC_IDR, AT91_RTC_ACKUPD | AT91_RTC_ALARM |
305 AT91_RTC_SECEV | AT91_RTC_TIMEV |
306 AT91_RTC_CALEV);
307 free_irq(AT91_ID_SYS, pdev);
308
309 rtc_device_unregister(rtc);
310 platform_set_drvdata(pdev, NULL);
311
312 return 0;
313}
314
315#ifdef CONFIG_PM
316
317/* AT91RM9200 RTC Power management control */
318
319static u32 at91_rtc_imr;
320
321static int at91_rtc_suspend(struct device *dev)
322{
323 /* this IRQ is shared with DBGU and other hardware which isn't
324 * necessarily doing PM like we are...
325 */
326 at91_rtc_imr = at91_sys_read(AT91_RTC_IMR)
327 & (AT91_RTC_ALARM|AT91_RTC_SECEV);
328 if (at91_rtc_imr) {
329 if (device_may_wakeup(dev))
330 enable_irq_wake(AT91_ID_SYS);
331 else
332 at91_sys_write(AT91_RTC_IDR, at91_rtc_imr);
333 }
334 return 0;
335}
336
337static int at91_rtc_resume(struct device *dev)
338{
339 if (at91_rtc_imr) {
340 if (device_may_wakeup(dev))
341 disable_irq_wake(AT91_ID_SYS);
342 else
343 at91_sys_write(AT91_RTC_IER, at91_rtc_imr);
344 }
345 return 0;
346}
347
348static const struct dev_pm_ops at91_rtc_pm = {
349 .suspend = at91_rtc_suspend,
350 .resume = at91_rtc_resume,
351};
352
353#define at91_rtc_pm_ptr &at91_rtc_pm
354
355#else
356#define at91_rtc_pm_ptr NULL
357#endif
358
359static struct platform_driver at91_rtc_driver = {
360 .remove = __exit_p(at91_rtc_remove),
361 .driver = {
362 .name = "at91_rtc",
363 .owner = THIS_MODULE,
364 .pm = at91_rtc_pm_ptr,
365 },
366};
367
368static int __init at91_rtc_init(void)
369{
370 return platform_driver_probe(&at91_rtc_driver, at91_rtc_probe);
371}
372
373static void __exit at91_rtc_exit(void)
374{
375 platform_driver_unregister(&at91_rtc_driver);
376}
377
378module_init(at91_rtc_init);
379module_exit(at91_rtc_exit);
380
381MODULE_AUTHOR("Rick Bronson");
382MODULE_DESCRIPTION("RTC driver for Atmel AT91RM9200");
383MODULE_LICENSE("GPL");
384MODULE_ALIAS("platform:at91_rtc");
1/*
2 * Real Time Clock interface for Linux on Atmel AT91RM9200
3 *
4 * Copyright (C) 2002 Rick Bronson
5 *
6 * Converted to RTC class model by Andrew Victor
7 *
8 * Ported to Linux 2.6 by Steven Scholz
9 * Based on s3c2410-rtc.c Simtec Electronics
10 *
11 * Based on sa1100-rtc.c by Nils Faerber
12 * Based on rtc.c by Paul Gortmaker
13 *
14 * This program is free software; you can redistribute it and/or
15 * modify it under the terms of the GNU General Public License
16 * as published by the Free Software Foundation; either version
17 * 2 of the License, or (at your option) any later version.
18 *
19 */
20
21#include <linux/bcd.h>
22#include <linux/clk.h>
23#include <linux/completion.h>
24#include <linux/interrupt.h>
25#include <linux/ioctl.h>
26#include <linux/io.h>
27#include <linux/kernel.h>
28#include <linux/module.h>
29#include <linux/of_device.h>
30#include <linux/of.h>
31#include <linux/platform_device.h>
32#include <linux/rtc.h>
33#include <linux/spinlock.h>
34#include <linux/suspend.h>
35#include <linux/time.h>
36#include <linux/uaccess.h>
37
38#include "rtc-at91rm9200.h"
39
40#define at91_rtc_read(field) \
41 readl_relaxed(at91_rtc_regs + field)
42#define at91_rtc_write(field, val) \
43 writel_relaxed((val), at91_rtc_regs + field)
44
45struct at91_rtc_config {
46 bool use_shadow_imr;
47};
48
49static const struct at91_rtc_config *at91_rtc_config;
50static DECLARE_COMPLETION(at91_rtc_updated);
51static DECLARE_COMPLETION(at91_rtc_upd_rdy);
52static void __iomem *at91_rtc_regs;
53static int irq;
54static DEFINE_SPINLOCK(at91_rtc_lock);
55static u32 at91_rtc_shadow_imr;
56static bool suspended;
57static DEFINE_SPINLOCK(suspended_lock);
58static unsigned long cached_events;
59static u32 at91_rtc_imr;
60static struct clk *sclk;
61
62static void at91_rtc_write_ier(u32 mask)
63{
64 unsigned long flags;
65
66 spin_lock_irqsave(&at91_rtc_lock, flags);
67 at91_rtc_shadow_imr |= mask;
68 at91_rtc_write(AT91_RTC_IER, mask);
69 spin_unlock_irqrestore(&at91_rtc_lock, flags);
70}
71
72static void at91_rtc_write_idr(u32 mask)
73{
74 unsigned long flags;
75
76 spin_lock_irqsave(&at91_rtc_lock, flags);
77 at91_rtc_write(AT91_RTC_IDR, mask);
78 /*
79 * Register read back (of any RTC-register) needed to make sure
80 * IDR-register write has reached the peripheral before updating
81 * shadow mask.
82 *
83 * Note that there is still a possibility that the mask is updated
84 * before interrupts have actually been disabled in hardware. The only
85 * way to be certain would be to poll the IMR-register, which is is
86 * the very register we are trying to emulate. The register read back
87 * is a reasonable heuristic.
88 */
89 at91_rtc_read(AT91_RTC_SR);
90 at91_rtc_shadow_imr &= ~mask;
91 spin_unlock_irqrestore(&at91_rtc_lock, flags);
92}
93
94static u32 at91_rtc_read_imr(void)
95{
96 unsigned long flags;
97 u32 mask;
98
99 if (at91_rtc_config->use_shadow_imr) {
100 spin_lock_irqsave(&at91_rtc_lock, flags);
101 mask = at91_rtc_shadow_imr;
102 spin_unlock_irqrestore(&at91_rtc_lock, flags);
103 } else {
104 mask = at91_rtc_read(AT91_RTC_IMR);
105 }
106
107 return mask;
108}
109
110/*
111 * Decode time/date into rtc_time structure
112 */
113static void at91_rtc_decodetime(unsigned int timereg, unsigned int calreg,
114 struct rtc_time *tm)
115{
116 unsigned int time, date;
117
118 /* must read twice in case it changes */
119 do {
120 time = at91_rtc_read(timereg);
121 date = at91_rtc_read(calreg);
122 } while ((time != at91_rtc_read(timereg)) ||
123 (date != at91_rtc_read(calreg)));
124
125 tm->tm_sec = bcd2bin((time & AT91_RTC_SEC) >> 0);
126 tm->tm_min = bcd2bin((time & AT91_RTC_MIN) >> 8);
127 tm->tm_hour = bcd2bin((time & AT91_RTC_HOUR) >> 16);
128
129 /*
130 * The Calendar Alarm register does not have a field for
131 * the year - so these will return an invalid value.
132 */
133 tm->tm_year = bcd2bin(date & AT91_RTC_CENT) * 100; /* century */
134 tm->tm_year += bcd2bin((date & AT91_RTC_YEAR) >> 8); /* year */
135
136 tm->tm_wday = bcd2bin((date & AT91_RTC_DAY) >> 21) - 1; /* day of the week [0-6], Sunday=0 */
137 tm->tm_mon = bcd2bin((date & AT91_RTC_MONTH) >> 16) - 1;
138 tm->tm_mday = bcd2bin((date & AT91_RTC_DATE) >> 24);
139}
140
141/*
142 * Read current time and date in RTC
143 */
144static int at91_rtc_readtime(struct device *dev, struct rtc_time *tm)
145{
146 at91_rtc_decodetime(AT91_RTC_TIMR, AT91_RTC_CALR, tm);
147 tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year);
148 tm->tm_year = tm->tm_year - 1900;
149
150 dev_dbg(dev, "%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__,
151 1900 + tm->tm_year, tm->tm_mon, tm->tm_mday,
152 tm->tm_hour, tm->tm_min, tm->tm_sec);
153
154 return 0;
155}
156
157/*
158 * Set current time and date in RTC
159 */
160static int at91_rtc_settime(struct device *dev, struct rtc_time *tm)
161{
162 unsigned long cr;
163
164 dev_dbg(dev, "%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__,
165 1900 + tm->tm_year, tm->tm_mon, tm->tm_mday,
166 tm->tm_hour, tm->tm_min, tm->tm_sec);
167
168 wait_for_completion(&at91_rtc_upd_rdy);
169
170 /* Stop Time/Calendar from counting */
171 cr = at91_rtc_read(AT91_RTC_CR);
172 at91_rtc_write(AT91_RTC_CR, cr | AT91_RTC_UPDCAL | AT91_RTC_UPDTIM);
173
174 at91_rtc_write_ier(AT91_RTC_ACKUPD);
175 wait_for_completion(&at91_rtc_updated); /* wait for ACKUPD interrupt */
176 at91_rtc_write_idr(AT91_RTC_ACKUPD);
177
178 at91_rtc_write(AT91_RTC_TIMR,
179 bin2bcd(tm->tm_sec) << 0
180 | bin2bcd(tm->tm_min) << 8
181 | bin2bcd(tm->tm_hour) << 16);
182
183 at91_rtc_write(AT91_RTC_CALR,
184 bin2bcd((tm->tm_year + 1900) / 100) /* century */
185 | bin2bcd(tm->tm_year % 100) << 8 /* year */
186 | bin2bcd(tm->tm_mon + 1) << 16 /* tm_mon starts at zero */
187 | bin2bcd(tm->tm_wday + 1) << 21 /* day of the week [0-6], Sunday=0 */
188 | bin2bcd(tm->tm_mday) << 24);
189
190 /* Restart Time/Calendar */
191 cr = at91_rtc_read(AT91_RTC_CR);
192 at91_rtc_write(AT91_RTC_SCCR, AT91_RTC_SECEV);
193 at91_rtc_write(AT91_RTC_CR, cr & ~(AT91_RTC_UPDCAL | AT91_RTC_UPDTIM));
194 at91_rtc_write_ier(AT91_RTC_SECEV);
195
196 return 0;
197}
198
199/*
200 * Read alarm time and date in RTC
201 */
202static int at91_rtc_readalarm(struct device *dev, struct rtc_wkalrm *alrm)
203{
204 struct rtc_time *tm = &alrm->time;
205
206 at91_rtc_decodetime(AT91_RTC_TIMALR, AT91_RTC_CALALR, tm);
207 tm->tm_year = -1;
208
209 alrm->enabled = (at91_rtc_read_imr() & AT91_RTC_ALARM)
210 ? 1 : 0;
211
212 dev_dbg(dev, "%s(): %02d-%02d %02d:%02d:%02d %sabled\n", __func__,
213 tm->tm_mon, tm->tm_mday, tm->tm_hour, tm->tm_min, tm->tm_sec,
214 alrm->enabled ? "en" : "dis");
215
216 return 0;
217}
218
219/*
220 * Set alarm time and date in RTC
221 */
222static int at91_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm)
223{
224 struct rtc_time tm;
225
226 at91_rtc_decodetime(AT91_RTC_TIMR, AT91_RTC_CALR, &tm);
227
228 tm.tm_mon = alrm->time.tm_mon;
229 tm.tm_mday = alrm->time.tm_mday;
230 tm.tm_hour = alrm->time.tm_hour;
231 tm.tm_min = alrm->time.tm_min;
232 tm.tm_sec = alrm->time.tm_sec;
233
234 at91_rtc_write_idr(AT91_RTC_ALARM);
235 at91_rtc_write(AT91_RTC_TIMALR,
236 bin2bcd(tm.tm_sec) << 0
237 | bin2bcd(tm.tm_min) << 8
238 | bin2bcd(tm.tm_hour) << 16
239 | AT91_RTC_HOUREN | AT91_RTC_MINEN | AT91_RTC_SECEN);
240 at91_rtc_write(AT91_RTC_CALALR,
241 bin2bcd(tm.tm_mon + 1) << 16 /* tm_mon starts at zero */
242 | bin2bcd(tm.tm_mday) << 24
243 | AT91_RTC_DATEEN | AT91_RTC_MTHEN);
244
245 if (alrm->enabled) {
246 at91_rtc_write(AT91_RTC_SCCR, AT91_RTC_ALARM);
247 at91_rtc_write_ier(AT91_RTC_ALARM);
248 }
249
250 dev_dbg(dev, "%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__,
251 tm.tm_year, tm.tm_mon, tm.tm_mday, tm.tm_hour,
252 tm.tm_min, tm.tm_sec);
253
254 return 0;
255}
256
257static int at91_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
258{
259 dev_dbg(dev, "%s(): cmd=%08x\n", __func__, enabled);
260
261 if (enabled) {
262 at91_rtc_write(AT91_RTC_SCCR, AT91_RTC_ALARM);
263 at91_rtc_write_ier(AT91_RTC_ALARM);
264 } else
265 at91_rtc_write_idr(AT91_RTC_ALARM);
266
267 return 0;
268}
269/*
270 * Provide additional RTC information in /proc/driver/rtc
271 */
272static int at91_rtc_proc(struct device *dev, struct seq_file *seq)
273{
274 unsigned long imr = at91_rtc_read_imr();
275
276 seq_printf(seq, "update_IRQ\t: %s\n",
277 (imr & AT91_RTC_ACKUPD) ? "yes" : "no");
278 seq_printf(seq, "periodic_IRQ\t: %s\n",
279 (imr & AT91_RTC_SECEV) ? "yes" : "no");
280
281 return 0;
282}
283
284/*
285 * IRQ handler for the RTC
286 */
287static irqreturn_t at91_rtc_interrupt(int irq, void *dev_id)
288{
289 struct platform_device *pdev = dev_id;
290 struct rtc_device *rtc = platform_get_drvdata(pdev);
291 unsigned int rtsr;
292 unsigned long events = 0;
293 int ret = IRQ_NONE;
294
295 spin_lock(&suspended_lock);
296 rtsr = at91_rtc_read(AT91_RTC_SR) & at91_rtc_read_imr();
297 if (rtsr) { /* this interrupt is shared! Is it ours? */
298 if (rtsr & AT91_RTC_ALARM)
299 events |= (RTC_AF | RTC_IRQF);
300 if (rtsr & AT91_RTC_SECEV) {
301 complete(&at91_rtc_upd_rdy);
302 at91_rtc_write_idr(AT91_RTC_SECEV);
303 }
304 if (rtsr & AT91_RTC_ACKUPD)
305 complete(&at91_rtc_updated);
306
307 at91_rtc_write(AT91_RTC_SCCR, rtsr); /* clear status reg */
308
309 if (!suspended) {
310 rtc_update_irq(rtc, 1, events);
311
312 dev_dbg(&pdev->dev, "%s(): num=%ld, events=0x%02lx\n",
313 __func__, events >> 8, events & 0x000000FF);
314 } else {
315 cached_events |= events;
316 at91_rtc_write_idr(at91_rtc_imr);
317 pm_system_wakeup();
318 }
319
320 ret = IRQ_HANDLED;
321 }
322 spin_unlock(&suspended_lock);
323
324 return ret;
325}
326
327static const struct at91_rtc_config at91rm9200_config = {
328};
329
330static const struct at91_rtc_config at91sam9x5_config = {
331 .use_shadow_imr = true,
332};
333
334#ifdef CONFIG_OF
335static const struct of_device_id at91_rtc_dt_ids[] = {
336 {
337 .compatible = "atmel,at91rm9200-rtc",
338 .data = &at91rm9200_config,
339 }, {
340 .compatible = "atmel,at91sam9x5-rtc",
341 .data = &at91sam9x5_config,
342 }, {
343 /* sentinel */
344 }
345};
346MODULE_DEVICE_TABLE(of, at91_rtc_dt_ids);
347#endif
348
349static const struct at91_rtc_config *
350at91_rtc_get_config(struct platform_device *pdev)
351{
352 const struct of_device_id *match;
353
354 if (pdev->dev.of_node) {
355 match = of_match_node(at91_rtc_dt_ids, pdev->dev.of_node);
356 if (!match)
357 return NULL;
358 return (const struct at91_rtc_config *)match->data;
359 }
360
361 return &at91rm9200_config;
362}
363
364static const struct rtc_class_ops at91_rtc_ops = {
365 .read_time = at91_rtc_readtime,
366 .set_time = at91_rtc_settime,
367 .read_alarm = at91_rtc_readalarm,
368 .set_alarm = at91_rtc_setalarm,
369 .proc = at91_rtc_proc,
370 .alarm_irq_enable = at91_rtc_alarm_irq_enable,
371};
372
373/*
374 * Initialize and install RTC driver
375 */
376static int __init at91_rtc_probe(struct platform_device *pdev)
377{
378 struct rtc_device *rtc;
379 struct resource *regs;
380 int ret = 0;
381
382 at91_rtc_config = at91_rtc_get_config(pdev);
383 if (!at91_rtc_config)
384 return -ENODEV;
385
386 regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
387 if (!regs) {
388 dev_err(&pdev->dev, "no mmio resource defined\n");
389 return -ENXIO;
390 }
391
392 irq = platform_get_irq(pdev, 0);
393 if (irq < 0) {
394 dev_err(&pdev->dev, "no irq resource defined\n");
395 return -ENXIO;
396 }
397
398 at91_rtc_regs = devm_ioremap(&pdev->dev, regs->start,
399 resource_size(regs));
400 if (!at91_rtc_regs) {
401 dev_err(&pdev->dev, "failed to map registers, aborting.\n");
402 return -ENOMEM;
403 }
404
405 rtc = devm_rtc_allocate_device(&pdev->dev);
406 if (IS_ERR(rtc))
407 return PTR_ERR(rtc);
408 platform_set_drvdata(pdev, rtc);
409
410 sclk = devm_clk_get(&pdev->dev, NULL);
411 if (IS_ERR(sclk))
412 return PTR_ERR(sclk);
413
414 ret = clk_prepare_enable(sclk);
415 if (ret) {
416 dev_err(&pdev->dev, "Could not enable slow clock\n");
417 return ret;
418 }
419
420 at91_rtc_write(AT91_RTC_CR, 0);
421 at91_rtc_write(AT91_RTC_MR, 0); /* 24 hour mode */
422
423 /* Disable all interrupts */
424 at91_rtc_write_idr(AT91_RTC_ACKUPD | AT91_RTC_ALARM |
425 AT91_RTC_SECEV | AT91_RTC_TIMEV |
426 AT91_RTC_CALEV);
427
428 ret = devm_request_irq(&pdev->dev, irq, at91_rtc_interrupt,
429 IRQF_SHARED | IRQF_COND_SUSPEND,
430 "at91_rtc", pdev);
431 if (ret) {
432 dev_err(&pdev->dev, "IRQ %d already in use.\n", irq);
433 goto err_clk;
434 }
435
436 /* cpu init code should really have flagged this device as
437 * being wake-capable; if it didn't, do that here.
438 */
439 if (!device_can_wakeup(&pdev->dev))
440 device_init_wakeup(&pdev->dev, 1);
441
442 rtc->ops = &at91_rtc_ops;
443 ret = rtc_register_device(rtc);
444 if (ret)
445 goto err_clk;
446
447 /* enable SECEV interrupt in order to initialize at91_rtc_upd_rdy
448 * completion.
449 */
450 at91_rtc_write_ier(AT91_RTC_SECEV);
451
452 dev_info(&pdev->dev, "AT91 Real Time Clock driver.\n");
453 return 0;
454
455err_clk:
456 clk_disable_unprepare(sclk);
457
458 return ret;
459}
460
461/*
462 * Disable and remove the RTC driver
463 */
464static int __exit at91_rtc_remove(struct platform_device *pdev)
465{
466 /* Disable all interrupts */
467 at91_rtc_write_idr(AT91_RTC_ACKUPD | AT91_RTC_ALARM |
468 AT91_RTC_SECEV | AT91_RTC_TIMEV |
469 AT91_RTC_CALEV);
470
471 clk_disable_unprepare(sclk);
472
473 return 0;
474}
475
476static void at91_rtc_shutdown(struct platform_device *pdev)
477{
478 /* Disable all interrupts */
479 at91_rtc_write(AT91_RTC_IDR, AT91_RTC_ACKUPD | AT91_RTC_ALARM |
480 AT91_RTC_SECEV | AT91_RTC_TIMEV |
481 AT91_RTC_CALEV);
482}
483
484#ifdef CONFIG_PM_SLEEP
485
486/* AT91RM9200 RTC Power management control */
487
488static int at91_rtc_suspend(struct device *dev)
489{
490 /* this IRQ is shared with DBGU and other hardware which isn't
491 * necessarily doing PM like we are...
492 */
493 at91_rtc_write(AT91_RTC_SCCR, AT91_RTC_ALARM);
494
495 at91_rtc_imr = at91_rtc_read_imr()
496 & (AT91_RTC_ALARM|AT91_RTC_SECEV);
497 if (at91_rtc_imr) {
498 if (device_may_wakeup(dev)) {
499 unsigned long flags;
500
501 enable_irq_wake(irq);
502
503 spin_lock_irqsave(&suspended_lock, flags);
504 suspended = true;
505 spin_unlock_irqrestore(&suspended_lock, flags);
506 } else {
507 at91_rtc_write_idr(at91_rtc_imr);
508 }
509 }
510 return 0;
511}
512
513static int at91_rtc_resume(struct device *dev)
514{
515 struct rtc_device *rtc = dev_get_drvdata(dev);
516
517 if (at91_rtc_imr) {
518 if (device_may_wakeup(dev)) {
519 unsigned long flags;
520
521 spin_lock_irqsave(&suspended_lock, flags);
522
523 if (cached_events) {
524 rtc_update_irq(rtc, 1, cached_events);
525 cached_events = 0;
526 }
527
528 suspended = false;
529 spin_unlock_irqrestore(&suspended_lock, flags);
530
531 disable_irq_wake(irq);
532 }
533 at91_rtc_write_ier(at91_rtc_imr);
534 }
535 return 0;
536}
537#endif
538
539static SIMPLE_DEV_PM_OPS(at91_rtc_pm_ops, at91_rtc_suspend, at91_rtc_resume);
540
541static struct platform_driver at91_rtc_driver = {
542 .remove = __exit_p(at91_rtc_remove),
543 .shutdown = at91_rtc_shutdown,
544 .driver = {
545 .name = "at91_rtc",
546 .pm = &at91_rtc_pm_ops,
547 .of_match_table = of_match_ptr(at91_rtc_dt_ids),
548 },
549};
550
551module_platform_driver_probe(at91_rtc_driver, at91_rtc_probe);
552
553MODULE_AUTHOR("Rick Bronson");
554MODULE_DESCRIPTION("RTC driver for Atmel AT91RM9200");
555MODULE_LICENSE("GPL");
556MODULE_ALIAS("platform:at91_rtc");